Ophthalmic illuminators allow a physician to illuminate the interior structure of the eye such as the vitreous and the retina during medical procedures. For example, an endoscopic ophthalmic illuminator (endo-illuminator) includes an optical fiber within the bore of a cannula. By driving a proximal of the optical fiber with a suitable light source, light emitted from a distal of the fiber illuminates the desired portion of the eye during a surgical procedure. Alternatively, a physician may illuminate the eye with fiber optic illumination while using an ophthalmic microscope.
A specialized ophthalmic illumination procedure has been developed to determine retinal fundus topography information. For example, a fundus camera has been configured to include a diffractive optical element (DOE) that projects a grid or line pattern onto the retina. To simplify the optical configuration, fundus lenses have been developed such as disclosed in U.S. Pat. No. 7,422,327 that include a volume hologram DOE that is illuminated off-axis. Such a DOE would thus be relatively transparent to the remaining on-axis optical lenses in the fundus camera. However, the off-axis illumination and the addition of the DOE lens still introduces some complexity for a fundus camera.
Accordingly, there is a need in the art for an improved ophthalmic illumination for retinal topography determinations.